You could first divide the group into:
And then divide the adults into:
We wish to perform two splits to divide integers into negative, zero, and positive. First zero and positive are split from the negatives, and then that group further split.
The flowchart shows how this works. One decision is nested inside the false branch of the first decision. A negative integer is correctly sorted out by the first decision. But a zero or positive integer goes through another decision to pick the correct category for it.
Are there other ways to do this?